[turbofan] Base more write barrier decisions on machine representation.

src/compiler/js-native-context-specialization.cc

Index: src/compiler/js-native-context-specialization.cc
diff --git a/src/compiler/js-native-context-specialization.cc b/src/compiler/js-native-context-specialization.cc
index b856e5de1e58697381dc21b31be7c8cf822746da..7fcbf626557ac546913b3237c5e645aea1a53792 100644
--- a/src/compiler/js-native-context-specialization.cc
+++ b/src/compiler/js-native-context-specialization.cc
@@ -966,7 +966,6 @@ JSNativeContextSpecialization::BuildPropertyAccess(
                                     control);
         }
       } else {
-        // DCHECK(field_type->Is(Type::Tagged()));
         DCHECK(rep == MachineRepresentation::kTagged);
       }
       Handle<Map> transition_map;